Conventional window guard locking devices are secured onto window guards for locking the window guards in position over a window of a building to prevent entry through the window. The window guards are hingedly mounted so that they can be opened when necessary as in the case of an emergency such as a fire.
The conventional window guard locking device has a cylindrical member provided with an outer annular recess and a central hole in communication therewith. A flange having a keyhole therethrough covering the annular recess and in alignment with the central hole is secured to the cylindrical member. A pin extends through the flange and into the bottom surface of the annular recess adjacent the central hole. A locking member in the form of a shaft having a pin adjacent the front end secured therein defining locking lobes is rotatably mounted in a hole in the window frame in alignment with the keyhole in the window guard locking device. An operating handle is mounted on the shaft inside the window to operate the shaft. Thus, with the window guard blocking device secured onto the window guard with the keyhole in a vertical position and the locking member in position with the locking lobes also in a vertical position, the window guard is closed so that the front end of the locking member extends into the central hole of the window guard locking device while the locking lobes extend through the keyhole into the annular recess whereafter the operating handle moves the locking member clockwise whereby the locking lobes move within the annular recess behind the flange until the upper locking lobe engages the pin at about a five-o'clock position thereby locking the window guard in position.
To open the window guard, the operating handle is moved counterclockwise which moves the locking lobes until they are aligned with the keyhole whereupon the locking member can now be free from the locking device by pushing open the window guard.
In the event of an emergency or some one attempts to open the device quickly, the locking lobes can be moved past the keyhole until the bottom locking lobe engages the pin which positions the locking lobes under the flange and not in alignment with the keyhole. In a panic, the operating handle will be moved back and forth to align the locking lobes with the keyhole. The time lost to align the locking lobes with the keyhole may prove to be disastrous.
Accordingly, the present invention overcomes the drawback of misalignment by manually aligning the locking lobes with the keyhole of a window guard locking device by positively aligning the locking lobes with the keyhole when the locking member is moved from a locked position to an unlocked position.